diff --git a/src/acme2.js b/src/acme2.js
index 538a058fa..4300b9c75 100644
--- a/src/acme2.js
+++ b/src/acme2.js
@@ -335,8 +335,8 @@ Acme2.prototype.downloadCertificate = async function (hostname, certUrl, certFil
     assert.strictEqual(typeof hostname, 'string');
     assert.strictEqual(typeof certUrl, 'string');
 
-    await promiseRetry({ times: 5, interval: 20000 }, async () => {
-        debug('downloadCertificate: downloading certificate');
+    await promiseRetry({ times: 5, interval: 20000, debug }, async () => {
+        debug(`downloadCertificate: downloading certificate of ${hostname}`);
 
         const result = await this.postAsGet(certUrl);
         if (result.statusCode === 202) throw new BoxError(BoxError.ACME_ERROR, 'Retry downloading certificate');
diff --git a/src/promise-retry.js b/src/promise-retry.js
index c2a47772f..ff59b9f49 100644
--- a/src/promise-retry.js
+++ b/src/promise-retry.js
@@ -17,6 +17,7 @@ async function promiseRetry(options, asyncFunction) {
             return await asyncFunction();
         } catch (error) {
             if (i === times - 1) throw error;
+            if (options.debug) options.debug(`Attempt ${i+1} failed. Will retry: ${error.message}`);
             await delay(interval);
         }
     }